Dr. Carruthers feels bitter at being betrayed by his employers, Heath and Morton, when they became rich as a result of a product he devised. He gains revenge by electrically enlarging bats and sending them out to kill his employers' family members by instilling in the bats a hatred for a particular perfume he has discovered, which he gets his victims to apply before going outdoors. Johnny Layton, a reporter, finally figures out Carruthers is the killer and, after putting the perfume on himself, douses it on Carruthers in the hopes it will get him to give himself away. One of the two is attacked as the giant bat makes one of its screaming, swooping power dives.

When you think of old-school horror, Béla Lugosi’s name should come to mind because he was the icon of horror (Dracula). If you're a fan of Lugosi then watch “The Devil Bat” (1940) also known as “Killer Bats,” a black-and-white horror movie starring Lugosi and directed by Jean Yarbrough (“She-Wolf of London”). The film was produced by Poverty Row studio Producers Releasing Corporation (PRC) which was known for making mostly small-budget B-movies such as “Misbehaving Husbands” and “Baby Face Morgan.”

“The Devil Bat” also stars Suzanne Kaaren, Dave O'Brien, Guy Usher, Yolande Mallott, and Donald Kerr. Lugosi plays Dr. Paul Carruthers a “Dr. Jekyll-Mr. Hyde” like character, who has a devilish mad scientist side and a kind doctor side. Dr. Carruthers becomes enraged when he realizes that the cosmetic manufacturers, Henry Morton (Guy Usher) and Martin Heath (Edward Mortimer), have cheated him out of money on his well developed formulas. Lugosi seeks revenge on Heath and Morton by creating a weapon of giant killer bats. Using a scented oil he discovered in Tibet, Dr. Carruthers puts the oil in aftershave lotion and dispenses it among those close to Heath and Morton. The scent attracts the devil bat that kills those exposed with the scent. The first two victims are the sons of Heath. They have strange wounds on their body that no one can identify as the cause of death.

The murders attract tall, handsome newspaper reporter Johnny Layton (Dave O'Brien) and humorous photographer One-Shot McGuire (Donald Kerr). Layton catches sight of the bat, but no one believes the giant “devil” bat exists. Then Morton's son Don (Gene O'Donnell) is killed and has the same unknown wounds as the first two victims. Layton finds a bottle of aftershave in Don’s bathroom and recognizes the scent from the other victims. People then start to think Dr. Carruthers is responsible, but that idea is dismissed, especially by Heath’s daughter and the sister of the first two victims, Mary Heath (Suzanne Kaaren), because she is considers the doctor a kind old gentleman. Ironically Dr. Carruthers is called to help investigate every time the “devil” bat strikes. Dr. Carruthers profession as a chemist has developed into giant bat making and a medical doctor. He can do it all!

Layton is given a bottle of aftershave by Dr. Carruthers, which One-Shot McGuire uses, and is attacked by the “devil” bat. Layton kills it, and the doctor creates another "devil" bat. Soon Morton falls victim to the bat and Mary becomes the next target. The bat is unable to enter Mary’s room as Layton sneaks into Dr. Carruthers lab and spills the oil on the doctor. Forcing him at gunpoint to wait for the bat's arrival, Dr. Carruthers struggles with Layton and runs into the night. Watch the film and see if Dr. Carruthers becomes a victim of his own creation.

Lugosi’s facial expressions and accent seemed to suit his vindictive doctor role very well. I particularly liked the tone he uses to tell his soon-to-be victims “goodbye” rather than “goodnight.” The bats themselves are typical of special effects from the era, but it is worth the watch. “The Devil Bat” tale moves along at a reasonable pace considering it’s only a little over an hour long. The film is pretty entertaining and something the whole family can enjoy. I doubt any children will get nightmares watching this film.